z400 or 400ex chassied 300ex????

It's for my Girlfriend so it NEEDS to have electric start and reverse. I'm a loyal Honda guy but the white Z is real nice. It will be used for Trails, XC, and some MX. Either one will have +1 a-arms. XC setup with an adjustable axle. The 300ex motor will be worked to 350cc. But the Z would just have Pipe, jets, and filter. she has already out grown my 300ex so we need to go bigger. I will not get anything else besides these two. I already have the 300ex motor and electronics so I would just need a 400ex rolling chassis.

What do you guys think?

Why arn't you considering the 400ex. I am 14 and can handle it fine. I know the power isn't too much for her if she has outgrown a 300ex.

NEEDS to have electric start and reverse

Z400 has better suspension and power. Easy decision if you ask me. My buddy has had a Z almost 2 years now and never had a problem with it. They are great bikes.

i would do the 300ex into a 400ex if i had to choose.